Cam controlled work holder



Nov. 27, 1951 c. ULFVES 2,576,707

CAM CONTROLLED WORK HOLDER Filed Sept. 18, 1950 2 SHEETS-SHEET 1INVENTOR. 64m A. (/L F'l/ES Nov. 27, 1951 c. A. ULFVES 2,576,707

CAM CONTROLLED WORK HOLDER Filed Sept. 18, 1950 2 SHEETSSHEET 2 C424 A.(/AFl ES BY M PV;

47'7'0EWE y Patented Nov. 27, 1951 2,576,707 CAM CONTROLLED WORK HOLDERCarl A. Ulfves, Worcester, Mass.

Application September 18 1950, Serial No. 185,442

This invention relates to a cam controlled work holder and the principalobject of the invent on resides in the provision of a device employlng aplurality of adjustable cams for moving engagement with a fixed fence orthe like and including a base and work holder thereon whereby the devicemay be moved with the cams in contact with the fence imparting to thedevice a particular predetermined path of travel so that a work piecethereon may be accurately cut or ground depending on the formation andrelative adjustment of the cams.

Other objects and advantages of the invention will appear hereinafter. 1Reference is to be had to the accompanying drawings in which Fig. 1 is atop plan view of the device; Fig. 2 is a view in side elevation thereof;Fig. 3 is a section on line 3--3 of Fig. 1; Fig. 4 is an end view; Figs.5 and 6 illustrate the device in use; Fig. 7 is a sectional Viewillustrating the use i of an attachment; and

Fig. 8 is a bottom plan View of a base plug.

-A'base Il) may be provided for supporting thedevice under consideration'as on the bed of' a grinder or the like, and this base has slidablymounted thereon a pair of semi-circular cam 7 Claims. (Cl. 51-232) 2to-back to form essentially a rectangle, see Fig.6. A yoke or similardevice 38 may be used to clamp the work to the V-block and a set screw"of smaller size work pieces.

40 may be employed in said yoke to secure the work tightly thereby andto enable the clamping Of course; the V-block may be adjustablymoved'along plates 28 and may be clamped thereby in any desired positionalong the top plate 24.

The base plate In is provided with a guide rail or fence 42 which may besecured thereto in any desired way as by screws 44. This fence ispreferably provided with a lip or flange 46 taking into circular grooves43 in the camsand it will be observed that this construction providesthat the cams may be moved along or with respect to the fence, but willnot tend to become separated therefrom due to the overhanging flange 46.The V-block has an undercut 41 to accommodate flange 49 on the work W.

'Referring now to Fig. 5 and assuming that the work is clamped asdescribed, the top plate 24 is moved as for instance by handso that thecam surfaces engage the fence 42 and if the cams are spaced as shown inFig. 5 the path of movement of plate 24 can be only that of an oval andthe larger axis thereof is determined I by the degree of separation ofthe cams. Thereelements l2 and [4 each of which is provided with anaccurately ground flat diametrical face indicated at I6,'each said facehaving centrally thereof a semi-circular depression as [8 for thereception of a removable base held plug or the like 20, the latterhaving in its top surface a ball bearing indicated at 22 for a purposeto bedescribed.

A top plate 24 is provided with upwardly extending rectilinear sideflanges 26 to which are detachably secured clamping plates 28 for thepurpose of clamping a V-block 30 by means of slots 32 therein as bestshown in Fig. 4. The V-block is adapted to form a clamp for the work Wso as to center the same as desired but particularly in aligned axialrelation with the plug 20.

The two cams I2 and I4 are adjustably located and secured to plate 24 bymeans of fasteners such as screws 34 passing through slots 36 in thecams and. threaded into the top plate 24, see Fig. 3. Thus the twosemi-circular cams may be adjustable where desired to and from eachother. They may be placed together forming a circle as in Fig. 1, orthey may be separated to any degree desired, see Fig. 5, forming inessence an oval, They may be even turned backfore, the work will bemoved in a path relative to a fixed tool such as a grinding wheel so asto grind a smaller oval thereon.

The plug 20 defines the limits of movement of the device as long as itis in place, but it may be removed if desired. It will be observed thatthe ball bearing 22 projects slightly above .the

1 bottom surface of plate 24 and into a longitudinal slot in the bottomof plate 24 again guiding the top plate even though the cam may notbe inengagement with the plug. In other words, the device may be moved on theplate 10 but only as controlled by the plug and the cam surfaces againstthe fence 42.

As shown in Fig. 6, the cams may be reversed and, therefore, arectangular shape may be ground or cut on the work piece.

Fig. 7 illustrates a condition employing a removable plug 52 which maytake up the entire hole 53 in the plate 24 but which has a portionhaving a half surface or part having an exactly ground diametrical edge54. Johansson blocks may be used to correctly position, for instance,cam I2 from the surface 54, whereupon the plug is turned around from theFig. 1 position and cam l4 may then be accurately adjusted from saidsurface 54.

This plug is insertable and removable from top or bottom of plate 24,and fits snugly enough so that it will not fall through the plate.

It will be seen that this device may be used to accurately form or grindtools, particularly punches, and all shapes from a circle to an ovalhaving a relatively long major axis, are easily ground as well asrectangular shapes as illustrated in Fig. 6.

Havingthuspdescribed my invention, and the advantages'thereof, I do notwish to be limited to the details herein disclosed otherwise than as setforth in the claims, but what I claim is:

l. A device of the class described-comprising. a plate, a work holder onthe plate, a plurality of cams, means to adjustably secure. the cams tothe plate, each cam having an arceshaped edge surface and the camstogether defining an oval or the like shape to be reproduced on thework, and relatively stationary means to be engaged by the. cams remotefrom the arc-shaped edges thereof to impart a predetermined path oftravel to the plate and the work as the. plate is rotated relatively toa tool, and means constrainingv the. plate to the predetermined path.725

2. A1de,vice of the class described comprising a plate, a. work. holderon the. plate, a plurality of [camsfmeans to adjustably secure the camsto the plate, each cam having a curvedsurfaee and thecamstogetherdefining a shape to be repro f-d-ilned on the Work, andrelatively stationary means to be engaged. by the cams to impart agpredeterminedpath of travel. to they plate and the work. as the plate.is. rotated relativelyto a .tool, and means constraining the plate. tothe.

predetermined path, said last named means comprising a fixed plugWorking in a slot in. the plate, and located betweenthe cams so. that:the plate andwork may be traveled-only. according to the slot andbetween the cams.

3. A device of the class described comprising a plate, a pair ofsubstantially semi-circular earns adjustably secured thereto, a. workholder on the plate, a. fence for engagement with the cams as the plateis moved in a rotational man t, and e en a the p a to ro id ,f or movingthe Same in a restrictedpath, said cams being engageable withsaidmeanstolirnit the travel of the plate inrtwo directions, a slot. in

theplate, receiving the. said means, the slot ex- 50;

tending betweenthe cams sogthat theslot, means.

and earns completely define the path of the plate as it is rotated.

4. A device, of the classgdescribed comprising a P ate, ar or holde onthe plate, aplurality of cams, means to adjustably secure the ga ns tothe plate, each cam having a curved surface and the cams togetherdefining a shapeito be reproduced on the work, and relatively stati'qn-.ary means to be engaged'by the cams; to'irnpart a predetermined path oftravel to the plate and" the work as the plate is rotated relatively toa on the teem-ate en a in th lu nd 1395 the form of a cylinder in thehole and removable therefrom, said plug having a portion thereof in theform of a semi-cylindrical body having a diametrical, axial surface,said plug forming a zero point by the diametrical surface thereof bywhich to exactly measure the adjustment of the cams from a center pointat the center of the 5 A- device oi the classadescrihed comprising aplate, a work holder on the plate, a plurality .of substantiallysemi-circular cams, means to adjnstably secure the cams to the plate,said cams havingthe straight edges facing each other and Q' SLQQmStogether defining an oval shape to be reproduced onrthe work, andrelatively stationary means-tobe engaged by the cams to impartapredetermined path of travel to the plate and the Work as the plate isrotated relatively tq a to ql, said cams beingsemi-circular and lot d enat he at said m an in udin a fencefor engagement of the cams.

6,. A device of the class described comprising a base, a fence. thereon,a pair'of semircircular cams resting on the. base for en agement withthe fence, a to plate above the cams, meansto adi tab y e ur the cam toh top at and w k o de n heitop pla e ..a plu in the b se r sin heref mbetw n t ca s, mean tively-limiting the extent ofl'travfil of the topPlate th reby eachavin a s mi-.circ la recess to receive the plug, whenthecams are i st dto rm su stan ia c rcl ith the diametrical surfaces ofthe cams substantially contacting. each other- 'LA. dev e o t e clasdescri ed ompr si a base, a'fence thereomapair of semi-circular camsresting on the base for engagement with the fence, a top plate. abovethe cams, means to adjustably secure the. cams to the top plate, awork'holder' on'the top plate, and a removable central plug, having aground fiat; surfacein an axial plane with respect thereto for measurinthe distaneeof the cams from a center.

ARL

REFERENCES err-En- Ihejollewingreferencesare of recordin. the file, ofthis. patent:

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